In a prior art, an aerosol container is widely used for discharging various kind of agent such as a paint, a cleaner, a hair-conditioner, an aromatic, and an insecticide. In such a container, not only an effective ingredient of the paint etc., but also a pressurized gas or an evaporable solvent for discharging the ingredient as a mist to the out of the container. These pressurized gas and the evaporated solvent may still remain in the container after the container is discarded, being used out or rendering unnecessary. The container with its content remaining therein should not be burned to discard, since it may be exploded. Moreover, the above-mentioned ingredient may be harmful to human body. Accordingly, it is desirable that the contents such as the gas are released before the container is discarded.
When the used out or unnecessary container is discarded, several methods are taken for releasing the gas or effective ingredient in the prior art. One of the method is to bore a hole on a body of the container by using a nail, drill, etc., by hand. The other one is to use a special boring device for making a perforation from which the gas or the ingredient is discharged. However, the former method may cause a problem in view of safety or sanitation, since the discharged content such as the gas may fall on a person who execute the boring operation. It may also causes an another problem that contents such paint may be discharged together with the gas and soil the person or the place therearound. On the other hand, the latter method is not suitable for a personal or a home use, since it needs a place or cost for installing the device.
In order to solve the above mentioned problem, the Japanese Patent Laid Open No. 10 (1998)-53289 provides an aerosol container by which anybody can release the gas or the content remaining in the container with ease. As shown in FIG. 24, the container includes a cap 101 having a turbular body and a top plate connected thereto, and a container body 103 having a discharge head upwardly protruding through a stem, and a winding rim on which the cap is fitted. The top plate has a center portion which is depressed to step into the inside of the cap to form a recess 105 into which a caulking portion of a mounting cap is able to be fitted. At the center of the recess, a small-diameter, cylindrical protrusion 106 is formed for engaging with a nozzle portion 102 of the aerosol container, with a gas-discharging hole 206 being formed in a vicinity of a bottom of the cylindrical portion.
For releasing the gas in the container body of the aerosol container with such a cap, the cap is removed from a head of the container body, and recapped again in an inverted posture. As shown in FIG. 25, when an engagement portion formed around the recess is fitted and secured to the above-mentioned caulking portion, the discharge head is engaged into the cylindrical protrusion of the cap and depressed downwards, keeping a discharging state unless the cap is separated from the container body.
However, the above-mentioned container is troublesome, since the cap has to be removed from the container body and inverted to recap again. And also, at the time of releasing the cap mounted on the head portion of the container body is upwardly open, such that when the content such as paint is discharged accompanying with the gas, the content scatters upwardly, soiling the person and place therearound.
Moreover, the top plate of the cap has a complicated, concave and convex structure for keeping the release of the content with a user's hand free from the container. When such a cap is integrally made of synthetic resin, a mould for forming the cap has to have a complicated structure, increasing a cost for manufacture.
To solve such a problem, Japanese utility model Registration No. 3056237 discloses another aerosol container with a cap 221 enabling the release of the content, shown in FIG. 26. The cap, which is integrally made of synthetic resin, and comprises a tubular body having at its end means for engaging with a winding portion of a container body, and an inclined top wall which is connected to the tubular body and has a depression piece 110 connected by a hinge for depressing a depression head 111.
For discarding this container when it is used out or unnecessary, the user should hold the container body with one hand while with the cap putting on the container body, and press the depression piece 224 of the top plate of the cap by the other hand, such that a connection link for supporting the depression piece is broken, and the depression piece falls into the cap by turning on the hinge 225 so as to press a discharge head 226, from which the contents remaining in the container body such as the pressurized gas and the paint or the other component are discharged.
Due to the construction of this container, a substance ejected energetically from the discharge head strikes against the inside of the cap, and is confined initially within the cap, and then generally escaping from it to the outside through an aperture formed by tearing around the periphery of the depression piece. This structure contributes to prevent the contents from ejecting outside directly so as to scatter around and soil the person and place therearound. Particularly, the content is not blown strongly to the nearby person. However, according to the above-mentioned structure, after the depression piece is pressed into a discharging position by the finger and then it is released, the depression piece is not able to halt at the discharging position by itself, and returns to its original position by a pushing up force of the discharge head. Accordingly, it is not possible to discharge all of the remaining content automatically.
Japanese Patent Laid Open No. 2001-19067 discloses an aerosol container enabling the automatic release of the remaining content, which has a container body from a top of which an upwardly biased discharge head is protruding, and a cap having a turbular body with a lower end engaged to the upper end of the turbular body, and a top plate covering an upper surface of the turbular body. The top plate has a downwardly tapering peripheral portion and an upwardly convex center portion which may be elastically inverted into a concave or downwardly protruding posture so as to forcibly depress the discharge head by the inversion of the center portion. However, in this container, the center portion is possibly pushed into the inverted, concave posture by a contact of some object or miss-operation of the user, such that the content of the container is release in the period of use against the will of the user. Moreover, in a normal mode for gas-releasing, when the container is treated roughly, for example throwing into a garbage box before the gas exhaustion is completed, the inverted center portion of the top plate may return to an original shape due to the strike against other obstacle, such that the gas-releasing halts insufficiently.
Japanese Patent Laid Open No. 11(1999)-70986 discloses another aerosol container enabling the automatic release of the remaining content, which has a tilt-type container body from which a discharge stem is erecting, from which the content is discharged only when the discharge stem is tilt or inclined from a vertical posture, a discharge tube fitted on the discharge stem and having an outward flange on a lower end of the tube itself, and a cap having a top-closed peripheral wall for connecting with a top end of the container body, whereby the peripheral wall is provided at its one side with a pair of upper and lower split lines, between which a reversible engagement plate is formed for elastically turning over into the inside of the cap, and engaging with a depressed side of the outward flange when the discharge stem is tilt, to keep the tilt posture to keep on discharging. However, the structure of the cap is effective only for the tilt type container.